1. Field of the Invention
This invention relates generally to a mechanism facilitating the use of a circuit card with a computer system and, more particularly, to an ejection mechanism for disengaging a riser card from a backplane board.
2. Description of the Related Art
Computer systems are provided with a CPU and related logical circuitry that are typically mounted on a backplane board within a computer chassis. The backplane board is configured to be interfaced with a plurality of printed circuit board assemblies or circuit cards having various electronic components disposed thereon, such as processors or memory chips, to increase the functionality of a computer system. It is often desired to add, replace or remove circuit cards in a computer system if, for example, cards become defective or out of date. As a result, edge connectors are provided for detachably mounting circuit cards on an edge perpendicular to the surface of the backplane board.
While such arrangements securely hold the circuit card in electrical contact with the backplane board, they often make removal of a circuit card difficult. High extraction forces are often required to release the pins of the circuit card from the connector of the backplane board. This problem presents additional difficulty because circuit cards often have delicate componentry that should not be handled manually, thus leaving minimal available area for grasping the card. Furthermore, the situation is exacerbated by the fact that cards are often closely spaced together such that it is difficult to grip an individual card to pull it out of the connector.
To facilitate this removal, various solutions have been proposed for presenting an easier way for disengaging a circuit card from backplane board. In one method, a connector for a circuit card includes a built-in ejector. This method, however, suffers from distinct disadvantages. First, having a built-in ejector adds complexity and cost to a standard connector. Additionally, many built-in ejector designs are hard to use, thus not providing a significant advantage over manually removing the card. Another proposed solution is to place an ejector along the top edge of the circuit card. This provides convenient access to the ejector when multiple cards are installed adjacent to one another. Additionally, this solution provides a lever ejector that only requires rotation in order to remove the circuit card. Despite these advantages, this ejector arrangement requires an additional structure to provide a bearing surface for the lever. This structure is often placed on the backplane board and extend upward roughly the height of the circuit card. This adds cost and complexity to an ejector system. Further, securely attaching the structure to the backplane board to provide a stable bearing surface is difficult. Still further, top edge ejectors typically are relatively small and provide a limited mechanical advantage for disengaging a circuit card.
Thus, what is needed is an apparatus to facilitate disengaging a circuit card edge connector from the electrical connector of the backplane board of a computer system. The apparatus should be easily accessible and operable to lift the pins of an attached circuit card substantially out of a socket connector for a backplane board. Further, the apparatus should be configured to be easily mounted on a circuit card.
It is thus an object of the present invention to provide an ejector apparatus for effectively disengaging a circuit board from a backplane board such that the circuit board can be easily removed from a computer system. It is a further object of the present invention to provide such an apparatus with a lever to provide sufficient leverage to move the pins of an attached circuit card substantially out of a socket connector of a backplane board. It is a further object of the present invention to arrange the lever such that it is easily accessible when multiple circuit cards are installed on the backplane board. It is yet another object of the present invention to provide a simple structure that can easily be mounted on a circuit card. It is still a further object of the present invention to provide an apparatus that is cost efficient, simple, and universal such that it can be used with many circuit board and backplane designs, and any standard connector configuration.
To accomplish these objects, the present invention provides an apparatus for ejecting a circuit card, and preferably a vertically mounted riser card, from engagement with a backplane board. The apparatus comprises an elongate lever having an upper manipulation region and a lower abutting region, and further comprises an attachment means for pivotably mounting the elongate lever to a riser card.
The attachment means is positioned in a central region of the lever and is configured for pivotal connection with the riser card. As such the lever is movable from a first position wherein the edge connector of the riser card is seated in and electrically connected with the connector of the backplane board to a second position wherein the edge connector of the riser card is disengaged from the backplane board connector.
The elongate lever is generally a triangular-shaped member being configured for rotation about the pivot point, the pivot point being connected to the riser card with the attachment means. The upper manipulation region extends upward from the pivot point a sufficient distance as to create sufficient leverage for vertically disengaging the pins connectors of the riser card. Likewise, the lower abutting region extends downward from the pivot point a sufficient distance as to create an interference with the backplane board upon rotation of the lever towards the second disengaged position. The triangular shape of the elongate lever forms a lower abutting region having a narrower cross-section that the lever central region.
The present invention thus provides a simple and ergonomic method for ejecting a riser card from a backplane board. Such an apparatus is mounted to typical riser cards known in the art and does not require an additional bearing surface to be securely mounted on a backplane board. Further, the apparatus only requires a small pulling force to disengage and at least partially remove the riser card from the backplane board.